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分频相位分析技术在断层解释中的应用 被引量:2
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作者 王庆华 《工程地球物理学报》 2013年第6期896-899,共4页
相干技术通常是识别断层的常用方法,但在实际勘探过程中,常规的相干分析技术在识别复杂地质条件下的断裂系统有一定的不适应性。对此,本文开发了分频相位技术来解决常规相干的不适应性,利用分频突出断层响应的最优势频带,和相位对地层... 相干技术通常是识别断层的常用方法,但在实际勘探过程中,常规的相干分析技术在识别复杂地质条件下的断裂系统有一定的不适应性。对此,本文开发了分频相位技术来解决常规相干的不适应性,利用分频突出断层响应的最优势频带,和相位对地层产状变化敏感的特点,克服了传统相干对垂向断距小的断层识别能力不足的问题。并将该技术应用在上海平湖地区及辽东地区,证实了分频相位技术针对具体的目标研究区其优势频率的断层分布特征具有其独特的作用。 展开更多
关键词 分频相位 断层 地震解释 平湖 辽东
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用于星间激光干涉测量的分频相位计辅助弱光锁相
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作者 乐陶然 穆衡霖 +3 位作者 徐欣 谈宜东 尉昊赟 李岩 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第14期316-325,共10页
弱光锁相是星间激光干涉测距的重要环节,通过锁相环跟踪外差干涉光信号相位.受散粒噪声、激光频率噪声等各类噪声限制,锁相环内部本地振荡器信号与外差信号间存在一定相位差,而锁相环的鉴相范围只有正负半个周期,若相位差某时刻超过鉴... 弱光锁相是星间激光干涉测距的重要环节,通过锁相环跟踪外差干涉光信号相位.受散粒噪声、激光频率噪声等各类噪声限制,锁相环内部本地振荡器信号与外差信号间存在一定相位差,而锁相环的鉴相范围只有正负半个周期,若相位差某时刻超过鉴相范围,则本地振荡器在反馈调节下可能会进入错误的工作点,出现周跳,导致后续相位重构出错.本文提出了基于引力波探测背景的一种周跳诊断方法,在原锁相环基础上引入一个具有更大鉴相范围的辅助分频相位计,可以对锁相环是否出现周跳提供判断依据.结合已有的锁相环及噪声理论,建立了分频相位计的理论模型,以此数值模拟了分频相位计工作,模拟结果表明,分频相位计可以实现大范围鉴相,具有判断弱光锁相周跳的能力. 展开更多
关键词 空间引力波探测 弱光锁相 周跳 分频相位
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基于多相位量化噪声抑制的分数频率合成器的实现 被引量:1
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作者 王皓磊 仲顺安 党华 《北京理工大学学报》 EI CAS CSCD 北大核心 2014年第11期1181-1185,共5页
为抑制Σ-△调制器量化噪声对分数频率合成器输出噪声的影响,提出一种基于多相位分数分频器的频率合成器结构.该结构可以避免毛刺并且主要电路模块不需要工作在高频,从而相应节省了功耗,同时分频器的输入可以不需要50%的占空比.通过对... 为抑制Σ-△调制器量化噪声对分数频率合成器输出噪声的影响,提出一种基于多相位分数分频器的频率合成器结构.该结构可以避免毛刺并且主要电路模块不需要工作在高频,从而相应节省了功耗,同时分频器的输入可以不需要50%的占空比.通过对比发现,对于环路带宽为1MHz的宽带情况下的Σ-△分数频率合成器,多相位分频器技术可以减小频率合成器输出频谱的相位噪声达12dB.该频率合成器使用UMC 0.18μm CMOS工艺实现,仿真结果证明它可以满足DVB-H系统协议指标要求. 展开更多
关键词 Σ-Δ调制器 分数频率合成器 量化噪声抑制技术 相位分数分频
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地震资料频变剩余相位校正技术及其在渤海BZ油田的应用
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作者 明君 周建科 +1 位作者 彭刚 王建立 《中国海上油气》 CAS CSCD 北大核心 2023年第4期66-75,共10页
在井震标定及子波分析时,发现渤海BZ油田的地震资料存在剩余相位,且其随频率变化显著,而地震层位解释和储层研究要求叠后地震资料不应该存在剩余相位,因此必须对地震数据的频变相位进行校正。但是,常相位校正技术并不能有效消除具有频... 在井震标定及子波分析时,发现渤海BZ油田的地震资料存在剩余相位,且其随频率变化显著,而地震层位解释和储层研究要求叠后地震资料不应该存在剩余相位,因此必须对地震数据的频变相位进行校正。但是,常相位校正技术并不能有效消除具有频变特征的剩余相位,本文研究提出了井约束下频变剩余相位校正技术,并在渤海BZ油田地震资料处理中进行了应用。频变剩余相位校正技术首先利用高斯滤波器分别对井旁地震道、零相位合成记录进行分频处理;然后基于最大相似系数准则,利用分频后的合成记录求出每个分频地震数据的剩余相位并进行常相位校正;最后将所有相位校正后的分频地震数据进行叠加得到最终分频相位校正结果。渤海BZ油田地震资料经过该方法处理后,有效消除了频变剩余相位的影响,地震资料品质得到显著改善,断层更加清晰,分辨率得到提升。因此,该技术可推广应用到具有类似特征的地震资料处理中。 展开更多
关键词 渤海 高斯滤波器 最大相似系数准则 频变剩余相位 分频相位校正 相位 地震资料处理
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注入式有源滤波器工程应用的关键技术 被引量:10
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作者 漆铭钧 罗安 刘定国 《电工技术学报》 EI CSCD 北大核心 2009年第3期195-202,共8页
注入式有源滤波器拓扑结构中的注入支路使得装置的有源部分承受的电网基波电压很小,因而适用于高电压、大容量谐波抑制的场合。但在实际工程应用中,由于注入支路的存在,出现了诸如要求基波谐振支路谐波分压小与要求谐波电流注入能力强... 注入式有源滤波器拓扑结构中的注入支路使得装置的有源部分承受的电网基波电压很小,因而适用于高电压、大容量谐波抑制的场合。但在实际工程应用中,由于注入支路的存在,出现了诸如要求基波谐振支路谐波分压小与要求谐波电流注入能力强之间的矛盾、直流侧电压持续抬升、注入支路对注入电流产生相移导致补偿精度低等问题。本文在进行了充分理论分析的基础上,提出了注入支路优化设计、PWM整流器控制直流侧电压、谐波电流分频相位补偿控制等方法,较好地解决了上述问题。文中的仿真分析和工程应用效果进一步证明了所提方法的可行性。 展开更多
关键词 注入式有源滤波器 基波谐振支路 直流侧电压控制 PWM整流器 分频相位补偿控制
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准噶尔盆地腹部永1井区层间断层处理技术 被引量:2
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作者 尚新民 江洁 +1 位作者 石林光 芮拥军 《石油地球物理勘探》 EI CSCD 北大核心 2007年第5期568-571,共4页
勘探表明,准噶尔盆地发现的绝大部分油气来源于深部二叠系烃源岩。由于盆地腹部深层层间断层一般断距较小、断点难以确定,利用常规地震资料难以识别与描述,因而无法对油气运移及富集区域做出准确预测。本文针对影响描述层间小断层的因... 勘探表明,准噶尔盆地发现的绝大部分油气来源于深部二叠系烃源岩。由于盆地腹部深层层间断层一般断距较小、断点难以确定,利用常规地震资料难以识别与描述,因而无法对油气运移及富集区域做出准确预测。本文针对影响描述层间小断层的因素采取了多项有针对性的措施:通过采用叠前时间偏移技术改善层间断层成像,为准确识别与描述层间断层奠定基础;通过地层倾角扫描技术细致刻画小断层;利用优势频带分频相位技术较好地实现了宽频带地震资料的断裂系统识别。综合利用上述方法准确识别与描述了永1井区深层层间断层,取得了良好的效果。 展开更多
关键词 层间断层 叠前偏移 地层倾角扫描 分频相位 油气运移通道
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多属性断层解释技术在煤层气储层解释中的应用 被引量:20
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作者 霍丽娜 张建军 +3 位作者 郑良合 丁清香 邵林海 吴新星 《石油地球物理勘探》 EI CSCD 北大核心 2014年第A01期221-227,10,共7页
断层的精细解释对煤层气开发井位部署至关重要。在韩城三维煤层气地震资料解释过程中,应用构造导向滤波技术提高地震数据的信噪比,在此基础上提取多种属性,增强了断层的识别能力。在该区综合应用GeoEast解释软件中的相干、方差、分频相... 断层的精细解释对煤层气开发井位部署至关重要。在韩城三维煤层气地震资料解释过程中,应用构造导向滤波技术提高地震数据的信噪比,在此基础上提取多种属性,增强了断层的识别能力。在该区综合应用GeoEast解释软件中的相干、方差、分频相位以及蚂蚁体等多种属性进行断裂解释,充分发挥不同属性的优势,解决了不同区域断裂解释和组合问题。多种属性的综合应用大大提高了断层的解释精度,为煤层气勘探开发井位部署提供了可靠的地质依据,据此调整了40余口井位坐标,后续钻井证实调整后的井位部署方案合理规避了断层的影响,提高了产气量。 展开更多
关键词 煤层气 构造导向滤波 相干 方差 分频相位 蚂蚁体
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A Novel Digital Transceiver for CT0 Standard 被引量:1
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作者 陈殿玉 许长喜 +7 位作者 陈浩琼 李振 郭秀丽 惠志强 施鹏 王跃 吴岳 熊绍珍 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第6期833-841,共9页
This paper introduces a novel digital transceiver for the cordless telephone zero (CT0) standard,which uses a digital modulation and demodulation technique to handle the signal instead of the traditional analog meth... This paper introduces a novel digital transceiver for the cordless telephone zero (CT0) standard,which uses a digital modulation and demodulation technique to handle the signal instead of the traditional analog meth-od. In the transmitter,a fractional-N phase locked loop (PLL) is utilized to realize the continuous phase frequency shift key (CPFSK) modulation,and a 2 Ts raised cosine (2RC) shaping technique is used to reduce the occupied bandwidth. In the receiver,a novel digital method is proposed to demodulate the 2RC CPFSK signal. This chip is fabricated using an SMIC 0.35μm mixed signal CMOS process with a die size of 2mm × 2mm. With an external low noise amplifier (LNA),the sensitivity of the chip is better than -103dBm. 展开更多
关键词 RF transceiver fractional-N PLL CPFSK MODULATOR DEMODULATOR
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Frequency synthesizer for DRM/DAB/AM/FM RF front-end
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作者 雷雪梅 王志功 +1 位作者 王科平 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期242-246,共5页
This paper describes a wideband low phase noise frequency synthesizer.It operates in the multi-band including digital radio mondiale DRM digital audio broadcasting DAB amplitude modulation AM and frequency modulation ... This paper describes a wideband low phase noise frequency synthesizer.It operates in the multi-band including digital radio mondiale DRM digital audio broadcasting DAB amplitude modulation AM and frequency modulation FM .In order to cover the signals of the overall frequencies a novel frequency planning and a new structure are proposed. A wide-band low-phase-noise low-power voltage-control oscillator VCO and a high speed wide band high frequency division ratio pulse swallow frequency divider with a low power consumption are presented.The monolithic DRM/DAB/AM/FM frequency synthesizer chip is also fabricated in a SMIC's 0.18-μm CMOS process.The die area is 1 425 μm ×795 μm including the test buffer and pads. The measured results show that the VCO operating frequency range is from 2.22 to 3.57 GHz the measured phase noise of the VCO is 120.22 dBc/Hz at 1 MHz offset the pulse swallow frequency divider operation frequency is from 0.9 to 3.4 GHz.The phase noise in the phase-locked loop PLL is-59.52 dBc/Hz at 10 kHz offset and fits for the demand of the DRM/DAB/AM/FM RF front-end. The proposed frequency synthesizer consumes 47 mW including test buffer under a 1.8 V supply. 展开更多
关键词 frequency synthesizer wideband voltage-controloscillator pulse swallow frequency divider low phase noise
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Implementation of a 6 GHz band TDD RF transceiver for the next generation mobile communication system 被引量:4
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作者 于志强 周健义 +2 位作者 赵丽 周飞 李江 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期276-281,共6页
The development of a high performance wideband radio frequency (RF) transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band an... The development of a high performance wideband radio frequency (RF) transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band and the channel bandwidth is up to 100 MHz. It operates in the time division duplex (TDD) mode and supports the multiple-input multipleoutput (MIMO) technique for the international mobile telecommunications (IMT)-advanced systems. The classical superheterodyne scheme is employed to achieve optimal performance. Design issues of the essential components such as low noise amplifier, power amplifier and local oscillators are described in detail. Measurement results show that the maximum linear output power of the RF transceiver is above 23 dBm, and the gain and noise figure of the low noise amplifier is around 24 dB and below 1 dB, respectively. Furthermore, the error vector magnitude (EVM) measurement shows that the performance of the developed RF transceiver is well beyond the requirements of the long term evolution (LTE)-advanced system. With up to 8 x 8 MIMO configuration, the RF transceiver supports more than a 1 Gbit/s data rate in field tests. 展开更多
关键词 radio frequency (RF) transceiver orthogonal frequency division multiplexing (OFDM) IMT-advanced system phase noise low noise amplifier power amplifier LTE-advanced system
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多属性预测技术在准噶尔盆地永1井地区的应用
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作者 裴磊 《内江科技》 2011年第3期108-108,155,共2页
准噶尔盆地永1井地区由于上部煤层的屏蔽作用,导致西山窑组储层的地震资料品质不理想,断裂系统与储层的发育特征预测难度较大。通过利用现有的各种地震、地质资料,建立该地区地震属性参数与地层岩性、物性特征变化及含油气性对应关系,... 准噶尔盆地永1井地区由于上部煤层的屏蔽作用,导致西山窑组储层的地震资料品质不理想,断裂系统与储层的发育特征预测难度较大。通过利用现有的各种地震、地质资料,建立该地区地震属性参数与地层岩性、物性特征变化及含油气性对应关系,采用地震多属性分析技术进行断裂系统与有效储层的预测,较好的识别出了该地区的微小断层发育特征,并落实了储层的平面展布。 展开更多
关键词 断裂系统 分频相位 多属性提取 西山窑组 准噶尔盆地
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Continuous frequency and phase spectrograms: a study of their 2D and 3D capabilities and application to musical signal analysis 被引量:1
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作者 Laurent NAVARRO Guy COURBEBAISSE Jean-Charles PINOLI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第2期199-206,共8页
A new lighting and enlargement on phase spectrogram (PS) and frequency spectrogram (FS) is presented in this paper. These representations result from the coupling of power spectrogram and short time Fourier transf... A new lighting and enlargement on phase spectrogram (PS) and frequency spectrogram (FS) is presented in this paper. These representations result from the coupling of power spectrogram and short time Fourier transform (STFT). The main contribution is the construction of the 3D phase spectrogram (3DPS) and the 3D frequency spectrogram (3DFS). These new tools allow such specific test signals as small slope linear chirp, phase jump case of musical signal analysis is reported. The main objective is to and small frequency jump to be analyzed. An application detect small frequency and phase variations in order to characterize each type of sound attack without losing the amplitude information given by power spectrogram 展开更多
关键词 Frequency spectrogram (FS) Phase spectrogram (PS) Time-frequency representations Musical signals
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A new phase comparison pilot protection based on wavelet transform
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作者 杨赢 邰能灵 郁惟慵 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第4期379-384,共6页
Current phase comparison based pilot protection had been generally utilized as primary protection of the transmission lines in China from the 1950's to the 1980' s, Comentional phase comparison pilot protection has ... Current phase comparison based pilot protection had been generally utilized as primary protection of the transmission lines in China from the 1950's to the 1980' s, Comentional phase comparison pilot protection has a long phase comparison time, which results in a longer fault-clearing time. This paper proposes a new current phase comparison, pilot protection scheme that is based on non-power frequency fauh eun'ent component. The phase of the fourth harmonic eun'ent of each end of the protected line has heen abstracted hy utilizing complex wavelet transformation and then compared in order to determine whether the inner fauh occurs or not. This way can greatly deerease fauh-elearing time and improve performances of this pilot protection when fault occurs under the heavy-load current and asymmetrical operation eonditions, Many EMTP simulations have verified the proposed scheme's correctness and effectiveness. 展开更多
关键词 pilot protection complex wavelet transient highfrequency component
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Phase Difference Method for DOA Estimation 被引量:2
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作者 陈志菲 孙进才 侯宏 《Journal of Marine Science and Application》 2010年第4期445-450,共6页
The phase difference method (PDM) is presented for the direction of arrival (DOA) estimation of the narrowband source. It estimates the DOA by measuring the reciprocal of the phase range of the sensor output spectra a... The phase difference method (PDM) is presented for the direction of arrival (DOA) estimation of the narrowband source. It estimates the DOA by measuring the reciprocal of the phase range of the sensor output spectra at the interest frequency bin. The peak width and variance of the PDM are presented. The PDM can distinguish closely spaced sources with different and unknown center frequencies as long as they are separated with at least one frequency bin. The simulation results show that the PDM has a better resolution than that of the conventional beamforming. 展开更多
关键词 direction of arrival(DOA) phase difference peak width variance RESOLUTION
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Focal—JMLab喇叭设计理念
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《现代音响技术》 2003年第3期57-61,共5页
关键词 聚焦时序 高音单体 W型音盆 JMLab公司 相位分频线路 Electra系列喇叭
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A NOVEL SEMI-BLIND TIME-FREQUENCY DOMAIN TRACKING ALGORITHM SUITABLE FOR MPSK-OFDM
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作者 Wei Li Xu Youyun Cai Yueming Pan Xiaofei 《Journal of Electronics(China)》 2008年第2期150-156,共7页
This paper presents a semi-blind tracking algorithm used for Multiple Phase Shift Keying based Orthogonal Frequency Division Multiplexing(MPSK-OFDM) system. By using special pream-bles to assist the decision of a feed... This paper presents a semi-blind tracking algorithm used for Multiple Phase Shift Keying based Orthogonal Frequency Division Multiplexing(MPSK-OFDM) system. By using special pream-bles to assist the decision of a feedback loop and to solve the problem of phase ambiguity,the tracking performance of the algorithm has been improved greatly. Only a few preambles are needed in the al-gorithm since the preambles are not used to estimate the frequency offset but used to provide the variation information of the phase due to the presence of frequency offset. Simulations verify that the algorithm has low SNR bound for tracking as well as high tracking accuracy and the tracking range is expanded to 30% of one subcarrier spacing. 展开更多
关键词 Phase ambiguity Multiple Phase Shift Keying based Orthogonal Frequency Division Multiplexing (MPSK-OFDM) SEMI-BLIND TRACKING
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时尚音乐至尊——惠威T600F
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《实用影音技术》 2003年第8期26-27,共2页
来自惠威音响的产品,心里总是有份独特的好感。因为不但惠威的扬声器音质优美,而且外观设计亦是美仑美奂。从震惊世界的皇家风范旗舰系列到荣获最高价值大奖的Diva系列;从尊贵专业豪庭系列到如今独具特色的时尚性感T系列;无不令人拍案叫... 来自惠威音响的产品,心里总是有份独特的好感。因为不但惠威的扬声器音质优美,而且外观设计亦是美仑美奂。从震惊世界的皇家风范旗舰系列到荣获最高价值大奖的Diva系列;从尊贵专业豪庭系列到如今独具特色的时尚性感T系列;无不令人拍案叫绝,无不叫人迷恋不已。因为惠威的产品不单是一款款音质优美的音响产品,更是一件件高贵精美的现代电声艺术品。 展开更多
关键词 惠威公司 T600F 音箱 三角形箱体 分离式相位修正分频网络
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Signal Separation and Instantaneous Frequency Estimation Based on Multi-scale Chirplet Sparse Signal Decomposition
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作者 于德介 罗洁思 史美丽 《Journal of Measurement Science and Instrumentation》 CAS 2010年第1期17-21,共5页
An approach based on multi-scale ehirplet sparse signal decomposition is proposed to separate the malti-component polynomial phase signals, and estimate their instantaneous frequencies. In this paper, we have generate... An approach based on multi-scale ehirplet sparse signal decomposition is proposed to separate the malti-component polynomial phase signals, and estimate their instantaneous frequencies. In this paper, we have generated a family of multi-scale chirplet functions which provide good local correlations of chirps over shorter time interval. At every decomposition stage, we build the so-called family of chirplets and our idea is to use a structured algorithm which exploits information in the family to chain chirplets together adaptively as to form the polyncmial phase signal component whose correlation with the current residue signal is largest. Simultaueously, the polynomial instantaneous frequency is estimated by connecting the linear frequency of the chirplet functions adopted in the current separation. Simulation experiment demonstrated that this method can separate the camponents of the multi-component polynamial phase signals effectively even in the low signal-to-noise ratio condition, and estimate its instantaneous frequency accurately. 展开更多
关键词 multi-scale chirplet base function multi-componentpolynomial phase signals instantaneous frequency signal- to noise ratio
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道集波形校正 被引量:4
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作者 王艳香 王圣 +3 位作者 张军舵 苏勤 邵喜春 冯心远 《地球物理学进展》 CSCD 北大核心 2014年第5期2266-2271,共6页
本文以广角反射道集、不同震源子波道集和CRP道集为研究对象,对这几种道集的子波进行了全面的分析,总结出它们都存在剩余相位问题.剩余子波相位可通过道集波形校正方法来解决:1.应用整形滤波方法对不同震源子波道集进行校正;2.应用小时... 本文以广角反射道集、不同震源子波道集和CRP道集为研究对象,对这几种道集的子波进行了全面的分析,总结出它们都存在剩余相位问题.剩余子波相位可通过道集波形校正方法来解决:1.应用整形滤波方法对不同震源子波道集进行校正;2.应用小时窗分频相位校正对广角反射记录和CRP道集进行校正.校正后解决了以下问题:不同震源子波道集由于震源子波不匹配而存在波形不一致问题;广角反射道集由于广角反射而存在的相位畸变问题;CRP道集由于实际地震记录和反褶积基本假设条件不完全一致而存在剩余子波相位问题;通过试验结果,都较好的消除了剩余子波相位成份,从而实现了同相叠加. 展开更多
关键词 广角反射道集 不同震源子波道集 CRP道集 小时窗分频相位校正 整形滤波
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Simple aspects of femtosecond stimulated Raman spectroscopy 被引量:1
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作者 ZHAO Bin NIU Kai +1 位作者 LI XiuTing LEE Soo-Ying 《Science China Chemistry》 SCIE EI CAS 2011年第12期1989-2008,共20页
Femtosecond stimulated Raman spectroscopy (FSRS), using an overlapping pair of narrow band Raman pump and broadband probe pulses with heterodyne detection along the probe pulse direction, is a new nonlinear spectros... Femtosecond stimulated Raman spectroscopy (FSRS), using an overlapping pair of narrow band Raman pump and broadband probe pulses with heterodyne detection along the probe pulse direction, is a new nonlinear spectroscopic technique to record vibrational spectra of even highly fluorescent molecules and to study vibrational dynamics on excited electronic states of molecules, as in photoisomerization. FSRS is described by diagrammatic third-order perturbation theory with wave packet analysis. The phase matching condition gives rise to forty-eight terms for FSRS, but the resonant condition reduces it to just eight terms, which can be depicted by Feynman dual time-line diagrams, or closed time path loop diagrams, or the complementary four-wave mixing energy level diagrams. The eight terms fall into four sets-SRS(I), SRS(Ⅱ), IRS(I), IRS(Ⅱ)-where SRS stands for stimulated Raman scattering and IRS stands for inverse Raman scattering. The SRS(I) set can also account for spontaneous Raman scattering, but the remaining SRS(Ⅱ), IRS(I) and IRS(Ⅱ) terms are only present in stimulated scattering with the presence of a probe field. The SRS(I) set accounts for the Stokes Raman lines while the IRS(I) term accounts for the anti-Stokes lines, relative to the Raman pump frequency, in the FSRS spectrum. The remaining SRS(Ⅱ) and IRS(Ⅱ) terms give rise to broad baselines. Using a harmonic oscillator model, analytic results are obtained for the four-time correlation functions in the third-order polarizations. The issue of high time and high frequency resolution in time-resolved FSRS spectra is discussed. Calculations are made with the theory to compare with experimental results for: (a) resonance FSRS of fluorescent Rhodamine 6G and (b) 2D-FSRS from a coherent vibrational state that has been prepared by an impulsive, off-resonant pump pulse on CDCl3. The calculated results compared well with experimental results, and in the case of 2D-FSRS on CDCl3 there is a dominant cascade effect contributing to the FSRS spectra. 展开更多
关键词 femtosecond stimulated Raman spectroscopy temporal and spectral resolution cascade effect
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